Perennial vegetables—crops that you plant just once and harvest year after year—are relatively rare in North American gardens.
With the exception of asparagus, rhubarb and artichokes, most gardeners are probably unaware of the tasty, extremely low-maintenance bounty that can be harvested when many annual crops aren’t available.
A Brief History of Perennial Crops
According to Perennial Vegetables by Eric Toensmeier, most North American gardening and farming traditions come from Europe, where there are very few perennial crops except fruits and nuts.
Cold and temperate Eurasian agriculture centered around livestock, annual grains and legumes, and early European settlers to North America simply brought their seeds and their cultivation methods with them, including draft animals for plowing up the soil every year.
However, in more temperate and tropical areas of the world, including much of North America, perennial root, starch and fruit crops were actively bred, selected and cultivated. These perennial crops were favored perhaps because they require less work to grow, and lacking large domesticated draft animals, only hand tools were available for farming.
Whatever the origin of our neglect of these amazing plants, we shouldn’t ignore these useful and productive foods any longer. Perennial vegetables should be much more widely available, especially because, compared to annual crops, they tend to be more nutritious, easier to grow, more ecologically beneficial, and less dependent on water and other inputs.
Benefits of Perennial Vegetables
Perennial Vegetables are Low Maintenance
Imagine growing vegetables that require just about the same amount of care as perennial flowers and shrubs—no annual tilling and planting. They thrive and produce abundant and nutritious crops throughout the season. Once established in the proper site and climate, perennial vegetables planted can be virtually indestructible despite neglect. Established perennials are often more resistant to pests, diseases, drought and weeds, too.
In fact, some perennials are so good at taking care of themselves that they require frequent harvesting to prevent them from becoming weeds themselves! The ease of cultivation and high yield is arguably the best reason for growing them.
Perennial Vegetables Extend the Harvest
Perennial vegetables often have different seasons of availability from annuals, which provides more food throughout the year. While you are transplanting tiny annual seedlings into your vegetable garden or waiting out the mid-summer heat, many perennials are already growing strong or ready to harvest.
Perennial Vegetables Can Perform Multiple Garden Functions
Many perennial vegetables are also beautiful, ornamental plants that can enhance your landscape. Others can function as hedges, groundcovers or erosion control for slopes. Other perennial veggies provide fertilizer to themselves and their neighboring plants by fixing nitrogen in the soil. Some can provide habitat for beneficial insects and pollinators, while others can climb trellises and provide shade for other crops.
Perennial Vegetables Help Build Soil
Perennial crops are simply amazing for the soil. Because they don’t need to be tilled, perennials help foster a healthy and intact soil food web, including providing habitat for a huge number of animals, fungi and other important soil life.
When well mulched, perennials improve the soil’s structure, organic matter, porosity and water-holding capacity.
Perennial vegetable gardens build soil the way nature intended by allowing the plants to naturally add more and more organic matter to the soil through the slow and stead decomposition of their leaves and roots. As they mature, they also help build topsoil and sequester atmospheric carbon.
Drawbacks of Perennial Vegetables
- Some perennial vegetables are slow to establish and may take several years to grow before they begin to yield well. (Asparagus is a good example of this.)
- Like many annuals, some perennial greens become bitter once they flower, therefore they are only available very early in the season.
- Some perennials have strong flavors which many Americans are unaccustomed to.
- Some perennials are so low-maintenance that they can quickly become weeds and overtake your garden, or escape and naturalize in your neighborhood. (Daylilies are a good example of this.)
- Perennials vegetables need to be careful placed into a permanent place in your garden, and will have to be maintained separately from your annual crops.
- Perennials have special pest and disease challenges because you can’t use crop rotation to minimize problems. Once some perennials catch a disease, they often have it forever, and need to be replaced.
Perennials Grown As Annuals
Some perennial crops are grown as annuals because they are easier to care for that way. For example, potatoes are technically perennials, but we grow them as annuals because pests and disease pressure in North America requires us to rotate potatoes often.
On the other hand, some plants we grow as annuals do quite well as perennials, like kale.
Cultivating Perennial Vegetables
One way to incorporate perennial veggies into your garden is to expand the edges of an already established garden. Simple extend an existing garden bed by 3 or 4 feet and plant a border of perennials there.
Or, if you already grow a perennial ornamental border or foundation shrubs, consider integrating some perennial vegetables, such as sea kale or sorrel. Many have attractive leaves or flowers to enhance the landscape.
You can also take advantage of currently unused areas of your landscape, matching the conditions to the appropriate perennial. There are some perennials, like wild leeks, that will grow in shady, wet or cool conditions where you couldn’t ordinarily grow food!
If you’re already growing perennial vegetables and want to take your garden or homestead to the next level, consider Permaculture gardening.
By imitating nature’s ecosystems, this approach promotes greater partnerships between plants, soil, insects and wildlife. In Permaculture designs, edible vegetables, herbs, fruiting shrubs and vines grow as an understory to taller fruit and nut trees. This technique is sometimes called “layering” or building a “guild.”
Layers or Guilds need to be built over a couple of years. In the first year, plant fruit trees as the outposts around your property. That same year and over the next several years, use sheet mulching to prepare planting areas beneath the trees for the understory plants. Sheet mulch a 2- to 3-foot-radius around each fruit tree the first year and gradually increase the mulched area as the trees grow.
After the first year, you can begin planting the mulched area with perennial vegetables, fruiting shrubs and vines. (For more on this method, see Gaia’s Garden: A Guide to Home-Scale Permaculture.)
20 Perennial Vegetables for North American Gardens
- raspberries, blueberries and other berry bushes
- kale (usually grown as an annual)
- garlic (usually grown as an annual)
- radicchio (usually grown as an annual)
- globe artichokes
But there are actually hundreds of perennial fruits and vegetables that will grow in temperate and warm climates like are found in North America!
Perennial Vegetables by Eric Toensmeier is the undisputed bible on this subject. With 241 full-color pages covering over 100 perennial crops that you can grow at home, you will be amazed and inspired to try something new in your garden every Spring!
For each plant, this gorgeous softcover reference includes range maps, color photos, climate and historical information, complete instructions for how to raise, tend and harvest, and even recipes and cooking ideas.
Perennial vegetables make the perfect complement to annuals in the garden, and this book will show you lots of ways to incorporate them into both your landscape and pantry.
Here are ten delicious, easy-to-grow perennial vegetables you may not know about yet. I’ve selected these from among dozens of perennial vegetables carefully described in Perennial Vegetables for taste, ease of cultivation and cooking, and broadest climate range.
Some of the following perennials grow wild in many parts of North America, but because they are over-harvested or they grow in fragile landscapes, it is usually better and more reliable to cultivate your own patch at home. That way you can also plant special cultivars of these wild edibles, carefully selected for taste and adapted for garden conditions. (See nursery list in Resources, below.)
No gardener or homesteader serious about growing their own food should be without some of these perennials in their landscape!
1. Bunching or Egyptian Onions
Some types of onions, such as the fall-planted bunching and Egyptian onions, continue to produce new onions even when some are harvested. The Egyptian onion (Allium cepa var. viviparum) produces small bulbils at the top of its stalk in late summer. You can use these tiny onions as they are, or plant them in the fall to grow more Egyptian onions. Zones 4-8.
As any gardener will tell you, daylilies (Hemerocallis spp.) thrive on neglect. So much so, they have naturalized across the United States. While they are primarily grown as ornamentals in North America, they are grown as a vegetable in Asia, harvested for their daily profusion of flower buds, which are used like green beans. The flowers themselves are served in salads or battered and fried. Zones 2-10.
3. Good King Henry
Good King Henry (Chenopodium bonus-henricus) is a traditional European vegetable known for its tasty shoots, leaves and flower buds. This spinach relative grows in full sun or partial shade and moist, well-drained soil. Harvest the tender shoots in spring. Hardy to Zone 3.
Native to eastern North America, groundnut (Apios Americana) is a nitrogen-fixing, 6-foot vine that bears high-protein tubers that taste like nutty-flavored potatoes. Grow groundnut vines near a shrub (as support) in a moist site that receives full sun or partial shade. Harvest in fall. Hardy to Zone 3.
5. Jerusalem Artichoke
In the same family as sunflowers, Jerusalem artichokes (Helianthus tuberosus, also called sunchokes) are grown for their underground tubers. You can eat them raw or cooked like potatoes. Their charming yellow flowers attract beneficial insects to the garden.
Jerusalem artichokes are vigorous plants that spread by underground rhizomes and may become difficult to eradicate. Some gardeners consider them invasive. Zones 4-9.
6. Ostrich Fern
Many gardeners grow Ostrich ferns (Matteuccia struthiopteris) for their ornamental value, not realizing that they can be grown for their delicious, early Spring fiddleheads, which are a coveted delicacy in fine dining restaurants nationwide. (Fiddleheads pictured at the top.) They love cool, shady spots and are very hardy from Zones 2-8.
7. Ramps or Wild Leeks
Ramps are an onion relative (Allium tricoccum) that grows wild in deciduous forests east of the Mississippi, emerging every Spring. They are a local delicacy that many people forage from the wild. How much easier to simply grow your own? Leaves and bulbs are both edible. Grow in a shady border in moist loam, or naturalize beneath trees. Hardy to Zone 4.
8. Scarlet Runner Beans
Scarlet runner beans (Phaseolus coccineus) are usually grown as ornamentals in most people’s gardens, but they are quite edible and nutritious, both as green beans and, later, as dried beans. The flowers, young leaves and tubers are also edible when cooked.
Some Scarlet Runner beans plants have been known to live 20 or more years, practically taking over a garden! Hardy to Zone 4.
9. Sea Kale
Sea Kale (Crambe maritime) is sometimes grown as an ornamental for its gray-blue leaves and white flowers on 3-foot-tall plants. The shoots, young leaves and flowers are edible, too. Hardy to Zone 4.
Sorrel is a perennial herb with tart, lemon-flavored leaves used for soups, stews, salads, and sauces. The two main sorrels grown are common sorrel, Rumex acetosa, and French sorrel, Rumex scutatus. They are relatives of rhubarb, and the leaves contain small amounts of oxalic acid that’s not harmful when consumed in small quantities, (unless you are sensitive to oxalates).
Sorrel tastes best in early spring; it becomes bitter as the weather warms. It’s a delicacy that is hard to find in markets because it wilts shortly after harvest. Garden sorrel is hardy to Zone 5; French sorrel is hardy to Zone 6.
Perennial seeds and plants can be hard to find, depending on where you live. Here are some resources to get you started.
- Plants for a Future International Nursery List
- Edible Landscaping – Afton, VA
- Oikos Tree Crops – Kalamazoo, MI
- Permaculture Nursery – Food Forest Farm; Holyoke, MA
- Forest Farm – Williams, OR
- Perennial Vegetables by Eric Toensmeier
- Gaia’s Garden: A Guide to Home-Scale Permaculture by Toby Hemenway